/*
* pool.c
* This code comes from jabberd - Jabber Open Source Server
* Copyright (c) 2002 Jeremie Miller, Thomas Muldowney,
* Ryan Eatmon, Robert Norris
* Copyright (C) 1998-1999 The Jabber Team http://jabber.org/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA02111-1307USA
*
* Copyrights
*
* Portions created by or assigned to Jabber.com, Inc. are
* Copyright (c) 1999-2002 Jabber.com, Inc. All Rights Reserved. Contact
* information for Jabber.com, Inc. is available at http://www.jabber.com/.
*
* Portions Copyright (c) 1998-1999 Jeremie Miller.
*
* Acknowledgements
*
* Special thanks to the Jabber Open Source Contributors for their
* suggestions and support of Jabber.
*
*/
/**
* @file pool.c
* @brief Handling of memory pools
*
* Jabberd handles its memory allocations in pools. You create a pool, can
* allocate memory from it and all allocations will be freed if you free
* the pool. Therefore you don't have to care that each malloc is freed,
* you only have to take care that the pool is freed.
*
* The normal call-flow for pools is:
*
* pool p = pool_new();
* struct mystruct *allocation1 = pmalloc(sizeof(struct mystruct));
* struct myotherstruct *allocation2 = pmalloc(sizeof(struct myotherstruct));
* ...
* pool_free(p);
*/
#include "libxode.h"
#define MAX_MALLOC_TRIES 10 /**< how many seconds we try to allocate memory */
#ifdef POOL_DEBUG
int pool__total = 0; /**< how many memory blocks are allocated */
int pool__ltotal = 0;
xht pool__disturbed = NULL;
/**
* create a new memory allocation and increment the pool__total counter
*
* only used if POOL_DEBUG is defined, else it is an alias for malloc
*
* @param size size of the memory to allocate
* @return pointer to the allocated memory
*/
void *_pool__malloc(size_t size)
{
pool__total++;
return malloc(size);
}
/**
* free memory and decrement the pool__total counter
*
* only used if POOL_DEBUG is defined, else it is an alias for free
*
* @param block pointer to the memory allocation that should be freed
*/
void _pool__free(void *block)
{
pool__total--;
free(block);
}
#else
#define _pool__malloc malloc /**< _pool__malloc updates pool__total counter if POOL_DEBUG is defined */
#define _pool__free free /**< _pool__free updates pool__total counter if POOL_DEBUG is defined */
#endif
/**
* try to allocate memory
*
* If allocation fails, it will be retries for MAX_MALLOC_TRIES seconds.
* If it still fails, we exit the process
*
* @param size how many bytes of memory we allocate
* @return pointer to the allocated memory
*/
inline void *_retried__malloc(size_t size) {
void *allocated_memory;
int malloc_tries = 0;
while ((allocated_memory=_pool__malloc(size)) == NULL) {
if (malloc_tries++ > MAX_MALLOC_TRIES) {
exit(999);
}
sleep(1); //pth_sleep(1);
}
return allocated_memory;
}
/**
* make an empty pool
*
* Use the macro pool_new() instead of a direct call to this function. The
* macro will create the parameters for you.
*
* @param zone the file in which the pool_new macro is called
* @param line the line in the file in which the pool_new macro is called
* @return the new allocated memory pool
*/
pool _pool_new(char *zone, int line)
{
// int malloc_tries = 0;
#ifdef POOL_DEBUG
int old__pool__total;
#endif
pool p = _retried__malloc(sizeof(_pool));
p->cleanup = NULL;
p->heap = NULL;
p->size = 0;
#ifdef POOL_DEBUG
p->lsize = -1;
p->zone[0] = '\0';
strcat(p->zone,zone);
snprintf(p->zone, sizeof(p->zone), "%s:%i", zone, line);
snprintf(p->name, sizeof(p->name), "%X", p);
if(pool__disturbed == NULL)
{
pool__disturbed = (xht)1; /* reentrancy flag! */
pool__disturbed = ghash_create(POOL_DEBUG,(KEYHASHFUNC)str_hash_code,(KEYCOMPAREFUNC)j_strcmp);
}
if(pool__disturbed != (xht)1)
ghash_put(pool__disturbed,p->name,p);
#endif
return p;
}
/**
* free a memory heap (struct pheap)
*
* @param arg which heep should be freed
*/
void _pool_heap_free(void *arg)
{
struct pheap *h = (struct pheap *)arg;
_pool__free(h->block);
_pool__free(h);
}
/**
* append a pool_cleaner function (callback) to a pool
*
* mem should always be freed last
*
* All appended pool_cleaner functions will be called if a pool is freed.
* This might be used to clean logically subpools.
*
* @param p to which pool the pool_cleaner should be added
* @param pf structure containing the reference to the pool_cleaner and links for the list
*/
void _pool_cleanup_append(pool p, struct pfree *pf)
{
struct pfree *cur;
if(p->cleanup == NULL)
{
p->cleanup = pf;
return;
}
/* fast forward to end of list */
for(cur = p->cleanup; cur->next != NULL; cur = cur->next);
cur->next = pf;
}
/**
* create a cleanup tracker
*
* this function is used to create a pfree structure that can be passed to _pool_cleanup_append()
*
* @param p the pool to which the pool_cleaner should be added
* @param f the function that should be called if the pool is freed
* @param arg the parameter that should be passed to the pool_cleaner function
* @return pointer to the new pfree structure
*/
struct pfree *_pool_free(pool p, pool_cleaner f, void *arg)
{
struct pfree *ret;
/* make the storage for the tracker */
ret = _retried__malloc(sizeof(struct pfree));
ret->f = f;
ret->arg = arg;
ret->next = NULL;
return ret;
}
/**
* create a heap and make sure it get's cleaned up
*
* pheaps are used by memory pools internally to handle the memory allocations
*
* @note the macro pool_heap calls _pool_new_heap and NOT _pool_heap
*
* @param p for which pool the heap should be created
* @param size how big the pool should be
* @return pointer to the new pheap
*/
struct pheap *_pool_heap(pool p, int size)
{
struct pheap *ret;
struct pfree *clean;
/* make the return heap */
ret = _retried__malloc(sizeof(struct pheap));
ret->block = _retried__malloc(size);
ret->size = size;
p->size += size;
ret->used = 0;
/* append to the cleanup list */
clean = _pool_free(p, _pool_heap_free, (void *)ret);
clean->heap = ret; /* for future use in finding used mem for pstrdup */
_pool_cleanup_append(p, clean);
return ret;
}
/**
* create a new memory pool and set the initial heap size
*
* @note you should not call this function but use the macro pool_heap instead which fills zone and line automatically
*
* @param size the initial size of the memory pool
* @param zone the file where this function is called (for debugging)
* @param line the line in the file where this function is called
* @return the new memory pool
*/
pool _pool_new_heap(int size, char *zone, int line)
{
pool p;
p = _pool_new(zone, line);
p->heap = _pool_heap(p,size);
return p;
}
/**
* allocate memory from a memory pool
*
* @param p the pool to use
* @param size how much memory to allocate
* @return pointer to the allocated memory
*/
void *pmalloc(pool p, int size)
{
void *block;
if(p == NULL)
{
fprintf(stderr,"Memory Leak! [pmalloc received NULL pool, unable to track allocation, exiting]\n");
abort();
}
/* if there is no heap for this pool or it's a big request, just raw, I like how we clean this :) */
if(p->heap == NULL || size > (p->heap->size / 2))
{
block = _retried__malloc(size);
p->size += size;
_pool_cleanup_append(p, _pool_free(p, _pool__free, block));
return block;
}
/* we have to preserve boundaries, long story :) */
if(size >= 4)
while(p->heap->used&7) p->heap->used++;
/* if we don't fit in the old heap, replace it */
if(size > (p->heap->size - p->heap->used))
p->heap = _pool_heap(p, p->heap->size);
/* the current heap has room */
block = (char *)p->heap->block + p->heap->used;
p->heap->used += size;
return block;
}
/**
* allocate memory and initialize the memory with the given char c
*
* @deprecated jabberd does use pmalloco instead, this function will be removed
*
* @param p which pool to use
* @param size the size of the allocation
* @param c the initialization character
* @return pointer to the allocated memory
*/
void *pmalloc_x(pool p, int size, char c)
{
void* result = pmalloc(p, size);
if (result != NULL)
memset(result, c, size);
return result;
}
/**
* allocate memory and initialize the memory with zero bytes
*
* easy safety utility (for creating blank mem for structs, etc)
*
* @param p which pool to use
* @param size the size of the allocation
* @return pointer to the allocated memory
*/
void *pmalloco(pool p, int size)
{
void *block = pmalloc(p, size);
memset(block, 0, size);
return block;
}
/**
* duplicate a string and allocate memory for it
*
* @todo efficient: move this to const char* and then loop through the existing heaps to see if src is within a block in this pool
*
* @param p the pool to use
* @param src the string that should be duplicated
* @return the duplicated string
*/
char *pstrdup(pool p, const char *src)
{
char *ret;
if(src == NULL)
return NULL;
ret = pmalloc(p,strlen(src) + 1);
strcpy(ret,src);
return ret;
}
/**
* when pstrdup() is moved to "const char*", this one would actually return a new block
*/
char *pstrdupx(pool p, const char *src)
{
return pstrdup(p, src);
}
/**
* get the size of a memory pool
*
* @param p the pool
* @return the size
*/
int pool_size(pool p)
{
if(p == NULL) return 0;
return p->size;
}
/**
* free a pool (and all memory that is allocated in it)
*
* @param p which pool to free
*/
void pool_free(pool p)
{
struct pfree *cur, *stub;
if(p == NULL) return;
cur = p->cleanup;
while(cur != NULL)
{
(*cur->f)(cur->arg);
stub = cur->next;
_pool__free(cur);
cur = stub;
}
#ifdef POOL_DEBUG
ghash_remove(pool__disturbed,p->name);
#endif
_pool__free(p);
}
/**
* public cleanup utils, insert in a way that they are run FIFO, before mem frees
*/
void pool_cleanup(pool p, pool_cleaner f, void *arg)
{
struct pfree *clean;
clean = _pool_free(p, f, arg);
clean->next = p->cleanup;
p->cleanup = clean;
}
#ifdef POOL_DEBUG
void debug_log(char *zone, const char *msgfmt, ...);
void _pool_stat(xht h, const char *key, void *data, void *arg)
{
pool p = (pool)data;
if(p->lsize == -1)
debug_log("pool_debug","%s: %s is a new pool",p->zone, p->name);
else if(p->size > p->lsize)
debug_log("pool_debug","%s: %s grew %d",p->zone, p->name, p->size - p->lsize);
else if((int)arg)
debug_log("pool_debug","%s: %s exists %d",p->zone,p->name, p->size);
p->lsize = p->size;
}
/**
* print memory pool statistics (for debugging purposes)
*
* @param full make a full report? (0 = no, 1 = yes)
*/
void pool_stat(int full)
{
if (pool__disturbed == NULL || pool__disturbed == (xht)1)
return;
ghash_walk(pool__disturbed,_pool_stat,(void *)full);
if(pool__total != pool__ltotal)
debug_log("pool_debug","%d\ttotal missed mallocs",pool__total);
pool__ltotal = pool__total;
return;
}
#else
/**
* dummy implementation: print memory pool statistics (for debugging purposes, real implementation if POOL_DEBUG is defined)
*
* @param full make a full report? (0 = no, 1 = yes)
*/
void pool_stat(int full)
{
return;
}
#endif